The field of the present invention relates to fuel injectors. In particular, fuel injectors are disclosed herein that can maintain a fuel flow rate that is substantially independent of fuel source pressure, or that can deliver fuel in a desired spray pattern.
A wide variety of fuel injectors have been disclosed previously. Some of those are described in:
U.S. Pat. No. 4,550,875 entitled “Electromagnetic unit fuel injector with piston assist solenoid actuated control valve” issued Nov. 5, 1985 to Teerman et al;
U.S. Pat. No. 4,572,433 entitled “Electromagnetic unit fuel injector” issued Feb. 25, 1986 to Deckard;
U.S. Pat. No. 4,693,424 entitled “Poppet covered orifice fuel injection nozzle” issued Sep. 15, 1987 to Sczomak;
U.S. Pat. No. 4,750,675 entitled “Damped opening poppet covered orifice fuel injection nozzle” issued Jun. 14, 1988 to Sczomak;
U.S. Pat. No. 4,813,610 entitled “Gasoline injector for an internal combustion engine” issued Mar. 21, 1989 to Renowden;
U.S. Pat. No. 4,852,853 entitled “Pressure balance type solenoid controlled valve” issued Aug. 1, 1989 to Toshio et al;
U.S. Pat. No. 5,088,467 entitled “Electromagnetic injection valve” issued Feb. 18, 1992 to Mesenich;
U.S. Pat. No. 5,191,867 entitled “Hydraulically-actuated electronically-controlled unit injector fuel system having variable control of actuating fluid pressure” issued Mar. 9, 1993 to Glassey;
U.S. Pat. No. 5,979,803 entitled “Fuel injector with pressure balanced needle valve” issued Nov. 9, 1999 to Peters et al;
U.S. Pat. No. 6,247,450 entitled “Electronic controlled diesel fuel injection system” issued Jun. 19, 2001 to Jiang;
U.S. Pat. No. 6,446,597 entitled “Fuel delivery and ignition system for operation of energy conversion systems” issued Sep. 10, 2002 to McAlister;
U.S. Pat. No. 6,435,429 entitled “Fuel injection valve” issued Aug. 20, 2002 to Eichendorf et al;
U.S. Pat. No. 6,725,838 entitled “Fuel injector having dual mode capabilities and engine using same” issued Apr. 27, 2004 to Shafer et al;
U.S. Pat. No. 7,083,126 entitled “Fuel injection arrangement” issued Aug. 1, 2006 to Lehtonen et al;
U.S. Pat. No. 7,350,539 entitled “Electromagnetic controlled fuel injection apparatus with poppet valve” issued Apr. 1, 2008 to Kaneko;
U.S. Pat. No. 7,353,806 entitled “Fuel injector with pressure balancing valve” issued Apr. 8, 2008 to Gant;
U.S. Pat. Pub. 2005/0151103 entitled “Method and apparatus for driving flow control electromagnetic proportional control valve” published Jul. 14, 2005 in the names of Kubota et al; and
U.S. Pat. Pub. 2008/0210199 entitled “Fuel injector” published Sep. 4, 2008 in the names of Zeng et al.
Each of the foregoing patent documents is hereby incorporated by reference as if fully set forth herein.
It would be desirable to provide a fuel injector having reduced dependence of fuel flow rate on fuel inlet pressure. It would be desirable to provide a fuel injector which has fuel flow rate which can be varied electronically during the injection. It would be desirable to provide a fuel injector having at least one spray-shaping surface to yield a desired fuel spray shape. Each of the foregoing patent references appears to lack those features.